[R] Functions in formulae ??

[Jeremy Clark]

Dear All,

In the following simple case I can't seem to get an improved fit,
despite trying all of the control possibilities. As there seem to be
no examples anywhere which show use of functions such as "dnorm"
within a formula, and as I am not confident at all that my formula is
correctly configured, I would appreciate some feedback ! Many thanks
in advance.

library(minpack.lm)

gg<-c(170,        171,      172,      173,      174,      175,
176,      177,      178,      179,      180,      181,      182,
183,      184,            185,      186,      187,      188,      189,
     190,      191,      192,      193,      194,      195,      196,
    197,      198,      199,            200,      201,      202,
203,      204,      205,      206,      207,      208,      209)

 dd<-c(1673,      1659,    1738,    1687,    1882,    2010,    2202,
 2248,    2409,    2417,    2215,    2279,    2539,    2479,    2341,
          2395,    2314,    2404,    2369,    2254,    2048,    1899,
  1892,    1744,    1333,    1183,    982,      772,      526,
451,            335,      253,      157,      108,      67,        44,
       26,        12,        10,        0)

 dd100000 <- dd * 0.00001

 dd100000gg <- data.frame(dd100000, gg)

 ## modLM4:

modLM4 <- nlsLM(dd100000 ~ dnorm(gg, mu,sigma, log = FALSE),  data =
dd100000gg, start = c(mu = 190, sigma = 10), trace = TRUE)

windows()
## plot data
plot(gg, dd100000, main = "modLM4")
## plot fitted values
lines(gg, fitted(modLM4), col = 2, lwd = 2)

On Thu, Nov 21, 2013 at 11:57 AM, Jeremy Clark <jeremyclarkmel at gmail.com> wrote:
> Dear All,
>
> In the following simple case I can't seem to get an improved fit,
> despite trying all of the control possibilities. As there seem to be
> no examples anywhere which show use of functions such as "dnorm"
> within a formula, and as I am not confident at all that my formula is
> correctly configured, I would appreciate some feedback ! Many thanks
> in advance.
>
> library(minpack.lm)
>
> gg<-c(170,        171,      172,      173,      174,      175,
> 176,      177,      178,      179,      180,      181,      182,
> 183,      184,            185,      186,      187,      188,      189,
>      190,      191,      192,      193,      194,      195,      196,
>     197,      198,      199,            200,      201,      202,
> 203,      204,      205,      206,      207,      208,      209)
>
>  dd<-c(1673,      1659,    1738,    1687,    1882,    2010,    2202,
>  2248,    2409,    2417,    2215,    2279,    2539,    2479,    2341,
>           2395,    2314,    2404,    2369,    2254,    2048,    1899,
>   1892,    1744,    1333,    1183,    982,      772,      526,
> 451,            335,      253,      157,      108,      67,        44,
>        26,        12,        10,        0)
>
>  dd100000 <- dd * 0.00001
>
>  dd100000gg <- data.frame(dd100000, gg)
>
>  ## modLM4:
>
> modLM4 <- nlsLM(dd100000 ~ dnorm(gg, mu,sigma, log = FALSE),  data =
> dd100000gg, start = c(mu = 190, sigma = 10), trace = TRUE)
>
> windows()
> ## plot data
> plot(gg, dd100000, main = "modLM4")
> ## plot fitted values
> lines(gg, fitted(modLM4), col = 2, lwd = 2)



-- 


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Jeremy Clark. Address: ul. Klonowica 45/2, 71-249 Szczecin, Poland.